ref_mtx

Outline

Reference mutex state.

C format

 ER      ref_mtx (ID mtxid, T_RMTX *pk_rmtx);
Parameter(s)

I/O

Parameter

Description

I

 ID      mtxid;
ID number of the mutex.

O

 T_RMTX  *pk_rmtx;
Pointer to the packet returning the mutex state.



[Mutex state packet: T_RMTX]

 typedef struct  t_rmtx {
     ID      htskid;         /*Existence of locked mutex*/
     ID      wtskid;         /*Existence of waiting task*/
 } T_RMTX;


Explanation

This service call stores the detailed information of the mutex specified by parameter mtxid (existence of locked mutexes, waiting tasks, etc.) into the area specified by parameter pk_rmtx.

- htskid
Stores whether a task that is locking a mutex exists.

TSK_NONE: No applicable task

Value: ID number of the task locking the mutex

- wtskid
Stores whether a task is queued to the mutex wait queue.

TSK_NONE: No applicable task

Value: ID number of the task at the head of the wait queue

Return value

Macro

Value

Description

E_OK

0

Normal completion.

E_ID

-18

Invalid ID number.

- mtxid < 0

- mtxid > VTMAX_MTX

E_CTX

-25

Context error.

- This service call was issued from a non-task.

- This service call was issued in the CPU locked state.

- This service call was issued in the status "PSW.IPL > kernel interrupt mask level".